The present invention is directed to motor terminal fixtures used in the testing of motor terminal connections.
Multi-phase motors such as those used in compressors require three phases of line voltage to be terminated across the motor coils of the compressor, typically using either three or six terminal connections in doing so. The intermediate wiring between a control panel and the compressor is housed in conduit and routed through various unit configurations. Additionally, the starter contacts are integral to the required wiring. The final assembly wiring and routing of the compressor line voltage must be verified as correct prior to shipping the unit.
The present invention provides a motor terminal test fixture for use in verifying the correctness of the final assembly wire and routing.
It is an object, feature and advantage of the present invention to solve the problems of the prior art.
It is an object, feature and advantage of the present invention to provide a motor terminal test fixture which is applied without error to terminals being tested. It is a further object, feature and advantage of the present invention to eliminate the requirement that a technician secure independent xe2x80x9calligatorxe2x80x9d style wiring harnesses or the like to the motor terminals. It is a further object, feature and advantage of the present invention to eliminate errors caused by incorrect installation of these alligator style clips.
It is an object, feature and advantage of the present invention to provide a motor terminal test fixture which includes strain relief cabling within the housing to prevent internal wear and to provide clamp release fittings for each terminal log to provide a secure fitting. It is a further object, feature and advantage of the present invention to provide press plates for each terminal which are individually spring loaded to maintain contact under vibration or lug position variances. It is a further object, feature and advantage of the present invention to provide a lever arm on the fixture to allow an easy-off/easy-on clamp by a technician. It is a further object, feature and advantage of the present invention to provide a polarity bar to ensure that inverted connections are not possible. It is another object, feature and advantage of the present invention to provide a quick connect/disconnect fixture which allows the fixture to be quickly and easily attached and quickly and easily replaced if necessary. It is a still further object, feature and advantage of the present invention to provide a test fixture which is compatible with both xe2x80x9cacross the linexe2x80x9d and xe2x80x9cwye-deltaxe2x80x9d starter types. It is yet another object, feature and advantage of the present invention to provide a test fixture which is easily disassembled to make repairs if necessary. Finally, it is an object, feature and advantage of the present invention to provide a motor tester which uses a simple voltage divider circuit to measure the resulting load at the motor terminals.
The present invention is directed to a motor test fixture for connection to motor terminal lugs. The fixture comprises: a housing including a plurality of external apertures positioned and formed to enclose the motor terminal lugs; an aperture in the housing; and a chamber within the housing having a first end open to the aperture. The fixture also comprises a slide bar moveably located in the chamber and moveable between at least a first position and a second position; a plurality of plates moveably mounted in the housing to move between a motor lug engagement position and a motor lug disengagement position; and a plurality of plate motivators. Each plate motivator is arranged on the slide bar to engage a respective one of the plates and, when the slide bar is in the first position, to motivate the respective plate to the lug disengagement position and, when the bar is in the second position, to motivate the respective plate to the lug engagement position.
The present invention is also directed to a slide bar. The slide bar comprises a longitudinally extending bar; and a plurality of plate motivators integrally formed in the bar where each plate motivator includes a sloped portion.
The present invention is further directed to a motor test fixture system. The system comprises a plurality of motor terminal lugs providing electrical connection to a motor and motor start contactors; a housing including a plurality of external apertures positioned and formed to enclose the motor terminal lugs; and a longitudinal chamber arranged within the housing and having a first chamber end and a second chamber end. The system also comprises a longitudinal slide bar arranged in the chamber and having a first end and a second end. The slide bar is moveable to a first position near the first chamber end and a second position nearer the second chamber end. The system further comprises a plurality of plates moveably positioned in the housing to move between a motor lug engagement position where the plates respectively contact a motor lug and a motor lug disengagement position where the plates do not contact the respective motor lug; and a plurality of plate motivators. Each plate motivator is arranged on the slide bar to engage a respective one of the plates when the slide bar is in the first position and to motivate the respective plate to the lug disengagement position.
The present invention still further provides a method of connecting a motor test fixture to motor terminal lugs. The method comprises the steps of: placing external apertures in the motor terminal test fixture over a plurality of motor terminal lugs; slideably moving a slide bar within a chamber in the test fixture from a first position to a second position; responsive to the slide bar movement, sliding a plurality of plates moveably mounted in the housing from a motor lug disengagement position to a motor lug engagement position; and providing a plurality of plate motivators associated with each of said plurality of plates respectively urging the respective plate to the lug disengagement position when the slide bar is in the first position and motivating the respective plate to the lug engagement position when the slide bar is in the second position.